[Fixes #13009] fix tests

Author: mattiagiupponi

geonode/services/forms.py

@@ -81,7 +81,7 @@ def clean(self):
                     base_url=url,
                     service_type=service_type,
                     username=self.cleaned_data.get("username", None),
-                    password=self.cleaned_data.get("password", ""),
+                    password=self.cleaned_data.get("password", None),
                 )
             except Exception as e:
                 logger.error(f"CreateServiceForm cleaning error: {e}")
@@ -97,6 +97,14 @@ def clean(self):
             self.cleaned_data["service_handler"] = service_handler
             self.cleaned_data["type"] = service_handler.service_type
 
+    def clean_username(self):
+        # the form return empty string, we want None if is not provided
+        return self.cleaned_data['username'] or None
+
+    def clean_password(self):
+        # the form return empty string, we want None if is not provided
+        return self.cleaned_data['password'] or None
+
 
 class ServiceForm(forms.ModelForm):
     title = forms.CharField(